891 resultados para Apatite concentrate


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Cosmological inflation is the dominant paradigm in explaining the origin of structure in the universe. According to the inflationary scenario, there has been a period of nearly exponential expansion in the very early universe, long before the nucleosynthesis. Inflation is commonly considered as a consequence of some scalar field or fields whose energy density starts to dominate the universe. The inflationary expansion converts the quantum fluctuations of the fields into classical perturbations on superhorizon scales and these primordial perturbations are the seeds of the structure in the universe. Moreover, inflation also naturally explains the high degree of homogeneity and spatial flatness of the early universe. The real challenge of the inflationary cosmology lies in trying to establish a connection between the fields driving inflation and theories of particle physics. In this thesis we concentrate on inflationary models at scales well below the Planck scale. The low scale allows us to seek for candidates for the inflationary matter within extensions of the Standard Model but typically also implies fine-tuning problems. We discuss a low scale model where inflation is driven by a flat direction of the Minimally Supersymmetric Standard Model. The relation between the potential along the flat direction and the underlying supergravity model is studied. The low inflationary scale requires an extremely flat potential but we find that in this particular model the associated fine-tuning problems can be solved in a rather natural fashion in a class of supergravity models. For this class of models, the flatness is a consequence of the structure of the supergravity model and is insensitive to the vacuum expectation values of the fields that break supersymmetry. Another low scale model considered in the thesis is the curvaton scenario where the primordial perturbations originate from quantum fluctuations of a curvaton field, which is different from the fields driving inflation. The curvaton gives a negligible contribution to the total energy density during inflation but its perturbations become significant in the post-inflationary epoch. The separation between the fields driving inflation and the fields giving rise to primordial perturbations opens up new possibilities to lower the inflationary scale without introducing fine-tuning problems. The curvaton model typically gives rise to relatively large level of non-gaussian features in the statistics of primordial perturbations. We find that the level of non-gaussian effects is heavily dependent on the form of the curvaton potential. Future observations that provide more accurate information of the non-gaussian statistics can therefore place constraining bounds on the curvaton interactions.

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The aim of this thesis was to study the seismic tomography structure of the earth s crust together with earthquake distribution and mechanism beneath the central Fennoscandian Shield, mainly in southern and central Finland. The earthquake foci and some fault plane solutions are correlated with 3-D images of the velocity tomography. The results are discussed in relation to the stress field of the Shield and with other geophysical, e.g. geomagnetic, gravimetric, tectonic, and anisotropy studies of the Shield. The earthquake data of the Fennoscandian Shield has been extracted from the Nordic earthquake parameter data base which was founded at the time of inception of the earthquake catalogue for northern Europe. Eight earlier earthquake source mechanisms are included in a pilot study on creating a novel technique for calculating an earthquake fault plane solution. Altogether, eleven source mechanisms of shallow, weak earthquakes are related in the 3-D tomography model to trace stresses of the crust in southern and central Finland. The earthquakes in the eastern part of the Fennoscandian Shield represent low-active, intraplate seismicity. Earthquake mechanisms with NW-SE oriented horizontal compression confirm that the dominant stress field originates from the ridge-push force in the North Atlantic Ocean. Earthquakes accumulate in coastal areas, in intersections of tectonic lineaments, in main fault zones or are bordered by fault lines. The majority of Fennoscandian earthquakes concentrate on the south-western Shield in southern Norway and Sweden. Onwards, epicentres spread via the ridge of the Shield along the west-coast of the Gulf of Bothnia northwards along the Tornio River - Finnmark fault system to the Barents Sea, and branch out north-eastwards via the Kuusamo region to the White Sea Kola Peninsula faults. The local seismic tomographic method was applied to find the terrane distribution within the central parts of the Shield the Svecofennian Orogen. From 300 local explosions a total of 19765 crustal Pg- and Sg-wave arrival times were inverted to create independent 3-D Vp and Vs tomographic models, from which the Vp/Vs ratio was calculated. The 3-D structure of the crust is presented as a P-wave and for the first time as an S-wave velocity model, and also as a Vp/Vs-ratio model of the SVEKALAPKO area that covers 700x800 km2 in southern and central Finland. Also, some P-wave Moho-reflection data was interpolated to image the relief of the crust-mantle boundary (i.e. Moho). In the tomography model, the seismic velocities vary smoothly. The lateral variations are larger for Vp (dVp =0.7 km/s) than for Vs (dVs =0.4 km/s). The Vp/Vs ratio varies spatially more distinctly than P- and S-wave velocities, usually from 1.70 to 1.74 in the upper crust and from 1.72 to 1.78 in the lower crust. Schist belts and their continuations at depth are associated with lower velocities and lower Vp/Vs ratios than in the granitoid areas. The tomography modelling suggests that the Svecofennian Orogen was accreted from crustal blocks ranging in size from 100x100 km2 to 200x200 km2 in cross-sectional area. The intervening sedimentary belts have ca. 0.2 km/s lower P- and S-wave velocities and ca. 0.04 lower Vp/Vs ratios. Thus, the tomographic model supports the concept that the thick Svecofennian crust was accreted from several crustal terranes, some hidden, and that the crust was later modified by intra- and underplating. In conclusion, as a novel approach the earthquake focal mechanism and focal depth distribution is discussed in relation to the 3-D tomography model. The schist belts and the transformation zones between the high- and low-velocity anomaly blocks are characterized by deeper earthquakes than the granitoid areas where shallow events dominate. Although only a few focal mechanisms were solved for southern Finland, there is a trend towards strike-slip and oblique strike-slip movements inside schist areas. The normal dip-slip type earthquakes are typical in the seismically active Kuusamo district in the NE edge of the SVEKALAPKO area, where the Archean crust is ca. 15-20 km thinner than the Proterozoic Svecofennian crust. Two near vertical dip-slip mechanism earthquakes occurred in the NE-SW junction between the Central Finland Granitoid Complex and the Vyborg rapakivi batholith, where high Vp/Vs-ratio deep-set intrusion splits the southern Finland schist belt into two parts in the tomography model.

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Binaural experiments are described which indicate that the ability of the brain to localize a desired sound and to suppress undesired sounds coming from other directions can be traced in part to the different times of arrival of a sound at the two ears. It is suggested that the brain inserts a time delay in one of the two nerve paths associated with the ears so as to be able to compare, and thus concentrate on, those sounds arriving at the ears with this particular time of arrival distance.The ability to perceive weak sounds binaurally in the presence of noise is shown to be a simple function of the direction of the desired sound and noise. An explanation is given for the effect reported by Koenig that front and rear confusion is avoided by head movements.

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Abstract (How the evaluating commentaries of a translation teacher reflect teacher knowledge): Teachers' knowledge has been found in research to be personal and experiential. In this article I discuss teacher knowledge from the perspective of a specific translation teacher. The aim of my study was to discover what kind of knowledge a translation teacher demonstrates when she evaluates her students’ translations. Focusing on attitude expressions in my qualitative analysis, I concentrate on an interview conducted with one teacher, who talks about her students’ translations. On this basis, one may conclude that the teacher’s knowledge is based on her experiences as both a teacher and a native speaker of Swedish.

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Since the second half of the 20th century, cancer has become a dominant disease in Western countries, endangering people regardless of age, gender, race or social status. Every year almost eight million people die of cancer worldwide. In Finland every fourth person is expected to fall ill with cancer at some stage of his or her life. During the 20th century, along with rapid changes in the medical system, people s awareness of cancer has increased a great deal. This has also influenced the image of cancer in popular discourse over the past decades. However, from the scientific point of view there is still much that is unclear about the disease. This thesis shows that this is a big problem for ordinary people, as, according to culture-bound illness ideology, people need an explanation about the origin of their illness in order to help them cope. The main aim of this thesis is to examine the process of being ill with cancer from the patient s point of view, in order to analyse attitudes and behaviour towards cancer and its significance and culture-bound images. This narrative-based study concentrates on patients voicings , which are important in understanding the cancer experience and when attempting to make it more open within current cultural and societal settings. The Kun sairastuin syöpään ( when I fell ill with cancer ) writing competition organised by Suomen Syöpäpotilaat ry (the Finnish Cancer Patients Association), Suomen Syöpäyhdistys ry (the Finnish Cancer Union), and Suomalaisen Kirjallisuuden Seuran kansanrunousarkisto (the Finnish Literary Society Folklore Archive) was announced on the 1st of May 1994 and lasted until the 30th of September 1994. As a result, a total of 672 cancer narratives, totalling 6384 pages, were received, filled with experiences relating to cancer. Written cancer narratives form a body of empirical data that is suitable for content or textual analysis. In this thesis, content analysis is adopted in order to become familiar with the texts and to preselect the themes and analytical units for further examination. I use multiple perspectives in order to interpret cancer patients ideas and reasoning. The ethnomedical approach unites popular health beliefs that originated in Finnish folk medicine, as well as connecting alternative medicine, which patients make use of, with biomedicine, the dominant form of medicine today. In addition to this, patients narratives, which are composed of various structural segments, are approached from the folklorist s perspective. In this way they can be seen as short pathographies, reconstructions of self-negotiation and individual decision making during the illness process. Above all, cancer patients writing describe their feelings, thoughts and experiences. Factors that appear insignificant to modern medicine, overwhelmed as it is by medical technologies that concentrate on dysfunctional tissue within diseased bodies. Ethnomedical study of cancer patients writings gives access to the human side of cancer discourse, and combines both medical, and popular, knowledge of cancer. In my view, the natural world and glimpses of tradition are bound together with one general aim within cancer narratives: to tackle the illness and mediate its meanings. Furthermore, the narrative approach reveals that participants write with the hope of offering a different interpretation of the cancer experience, and thus of confronting culturally pre-defined images and ideologies.

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Horseback riding is a popular activity in Finland, especially among young women and girls. For centuries, however, horse husbandry and horse culture in Finland had been dominated by men. Nowadays it is mainly the girls who ride as a hobby and take care of the horses. The stable has evolved into an important social sphere for girls, a semi-public room of their own where they spend time together. A study of the girl culture in the riding stable offers a unique perspective as well as new information on becoming a girl and a young woman in Finland. The subject of my research is the girl culture and girls communities at the horseback riding stables. In this thesis I discuss what kind of girl-cultural sphere the stable is, how girls organize their community, and what different aspects and meanings the hobby entails for girls while they are actively engaged in the hobby. I focus on the construction of gender and girlhood and examine how these gender constructions can be theorized as gender tradition. The research material consists of the interviews of 22 stable girls from different parts of Finland and an observation period at one of the stables. The informants were from 13 to 27 years of age. The theoretical background is based on the anthropological study of folklore, girls studies, feminist theory and post-humanist viewpoints. I am interested in how girls culture and girlhood are produced performatively in the interview narration and participant observation. I concentrate on four aspects of this culture: 1) what girls do at the stable, and what kind of relationships they create with horses; 2) social relations focusing on the ways girls construct their own groups, the way their hierarchy is constructed and how they use power; 3) the norms and social control regarding social behaviour; and 4) the reasons girls give for their involvement in the hobby, and girls interest in horses in general. In this girl culture, gender norms and boundaries are not only stretched or transgressed, but the culture also re-produces the hierarchical and stereotypical ideas of gender. The traditions of gender express both the hegemonic gender system and those ideas of gender which girls resist, at least momentarily. Constructions of gender and gender tradition are constituted at the intersections of historical and contemporary expectations of what it means to be a girl. Conscious of these societal demands, girls support, reproduce, challenge, and make comments on them.

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The aim of the study was to explore the importance of evaluating leadership criteria in Finland at leader/subordinate levels of the insurance industry. The overall purpose of the thesis is tackled and analyzed from two different perspectives: - by examining the importance of the leadership criteria and style of Finnish insurance business leaders and their subordinates - by examining the opinions of insurance business leaders regarding leadership criteria in two culturally different countries: the US and Finland. This thesis consists of three published articles that scrutinise the focal phenomena both theoretically and empirically. The main results of the study do not lend support to the existence of a universal model of leadership criteria in the insurance business. As a matter of fact, the possible model seems to be based more on the special organizational and cultural circumstances of the country in question. The leadership criteria seem to be quite stable irrespective of the comparatively short research time period (3–5 years) and hierarchical level (subordinate/leader). Leaders have major difficulties in changing their leadership style. In fact, in order to bring about an efficient organizational change in the company you have to alternate the leader. The cultural dimensions (cooperation and monitoring) identified by Finnish subordinates were mostly in line with those of their managers, whilst emphasizing more the aspect of monitoring employees, which could be seen from their point of view as another element of managers’ optimizing/efficiency requirements. In Finnish surveys the strong emphasis on cooperation and mutual trust become apparent by both subordinates and managers. The basic problem is still how to emphasize and balance them in real life in such a way that both parties are happy to work together on a common basis. The American surveys suggests hypothetically that in a soft market period (buyer’s market) managers employ a more relationship-oriented leadership style and correspondingly adapt their leadership style to a more task-oriented approach in a hard market phase (seller’s market). In making business better Finnish insurance managers could probably concentrate more on task-oriented items such as reviewing, budgeting, monitoring and goal-orientation. The study also suggests that the social safety net of the European welfare state ideology has so far shielded the culture-specific sense of social responsibility of Finnish managers from the hazards of free competition and globalization.

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In this thesis work, we design rigorous and efficient protocols/mechanisms for different types of wireless networks using a mechanism design [1] and game theoretic approach [2]. Our work can broadly be viewed in two parts. In the first part, we concentrate on ad hoc wireless networks [3] and [4]. In particular, we consider broadcast in these networks where each node is owned by independent and selfish users. Being selfish, these nodes do not forward the broadcast packets. All existing protocols for broadcast assume that nodes forward the transit packets. So, there is need for developing new broadcast protocols to overcome node selfishness. In our paper [5], we develop a strategy proof pricing mechanism which we call immediate predecessor node pricing mechanism (IPNPM) and an efficient new broadcast protocol based on IPNPM. We show the efficacy of our proposed broadcast protocol using simulation results.

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Service researchers have repeatedly claimed that firms should acquire customer information in order to develop services that fit customer needs. Despite this, studies that would concentrate on the actual use of customer information in service development are lacking. The present study fulfils this research gap by investigating information use during a service development process. It demonstrates that use is not a straightforward task that automatically follows the acquisition of customer information. In fact, out of the six identified types of use, four represent non usage of customer information. Hence, the study demonstrates that the acquisition of customer information does not guarantee that the information will actually be used in development. The current study used an ethnographic approach. Consequently, the study was conducted in the field in real time over an extensive period of 13 months. Participant observation allowed direct access to the investigated phenomenon, i.e. the different types of use by the observed development project members were captured while they emerged. In addition, interviews, informal discussions and internal documents were used to gather data. A development process of a bank’s website constituted the empirical context of the investigation. This ethnography brings novel insights to both academia and practice. It critically questions the traditional focus on the firm’s acquisition of customer information and suggests that this focus ought to be expanded to the actual use of customer information. What is the point in acquiring costly customer information if it is not used in the development? Based on the findings of this study, a holistic view on customer information, “information in use” is generated. This view extends the traditional view of customer information in three ways: the source, timing and form of data collection. First, the study showed that the customer information can come explicitly from the customer, from speculation among the developers or it can already exist implicitly. Prior research has mainly focused on the customer as the information provider and the explicit source to turn to for information. Second, the study identified that the used and non-used customer information was acquired both previously, and currently within the time frame of the focal development process, as well as potentially in the future. Prior research has primarily focused on the currently acquired customer information, i.e. within the timeframe of the development process. Third, the used and non-used customer information was both formally and informally acquired. In prior research a large number of sophisticated formal methods have been suggested for the acquisition of customer information to be used in development. By focusing on “information in use”, new knowledge on types of customer information that are actually used was generated. For example, the findings show that the formal customer information acquired during the development process is used less than customer information already existent within the firm. With this knowledge at hand, better methods to capture this more usable customer information can be developed. Moreover, the thesis suggests that by focusing stronger on use of customer information, service development processes can be restructured in order to facilitate the information that is actually used.

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We describe the on-going design and implementation of a sensor network for agricultural management targeted at resource-poor farmers in India. Our focus on semi-arid regions led us to concentrate on water-related issues. Throughout 2004, we carried out a survey on the information needs of the population living in a cluster of villages in our study area. The results highlighted the potential that environment-related information has for the improvement of farming strategies in the face of highly variable conditions, in particular for risk management strategies (choice of crop varieties, sowing and harvest periods, prevention of pests and diseases, efficient use of irrigation water etc.). This leads us to advocate an original use of Information and Communication Technologies (ICT). We believe our demand-driven approach for the design of appropriate ICT tools that are targeted at the resource-poor to be relatively new. In order to go beyond a pure technocratic approach, we adopted an iterative, participatory methodology.

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Multimedia mining primarily involves, information analysis and retrieval based on implicit knowledge. The ever increasing digital image databases on the Internet has created a need for using multimedia mining on these databases for effective and efficient retrieval of images. Contents of an image can be expressed in different features such as Shape, Texture and Intensity-distribution(STI). Content Based Image Retrieval(CBIR) is an efficient retrieval of relevant images from large databases based on features extracted from the image. Most of the existing systems either concentrate on a single representation of all features or linear combination of these features. The paper proposes a CBIR System named STIRF (Shape, Texture, Intensity-distribution with Relevance Feedback) that uses a neural network for nonlinear combination of the heterogenous STI features. Further the system is self-adaptable to different applications and users based upon relevance feedback. Prior to retrieval of relevant images, each feature is first clustered independent of the other in its own space and this helps in matching of similar images. Testing the system on a database of images with varied contents and intensive backgrounds showed good results with most relevant images being retrieved for a image query. The system showed better and more robust performance compared to existing CBIR systems

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The phyllite deposit of Degana, Rajasthan, containing tungsten values in the form of wolframite, (Fe, MnWO sub 4 ) finely dispersed in the quartz groundmass, has been quantitatively analysed to give 0.063% WO sub 3 , 6.66% Fe sub 2 O sub 3 , 14.30% Al sub 2 O sub 3 and 67.4% SiO sub 2 . The major gangue minerals identified are quartz, iron oxides and mica along with minor amounts of graphite, fluorite and sulphides. The amenability of the ore to gravity concentration, magnetic separation and a combination of the processes has been studied. A combination of tabling on --100 mesh ground ore and dry magnetic separation of the tabled concentrate gave a final concentrate containing 1.834% WO sub 3 with an overall recovery of only 4.6%. The complex mineralogy combined with fine dispersion of very low W values have contributed to the low recoveries and grades. Graph, photomicrographs. 10 ref.--AA

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Continuing urbanization is a crucial driver of land transformation, having widespread impacts on virtually all ecosystems. Terrestrial ecosystems, including disturbed ones, are dependent on soils, which provide a multitude of ecosystem services. As soils are always directly and/or indirectly impacted through land transformation, land cover change causes soil change. Knowledge of ecosystem properties and functions in soils is increasing in importance as humans continue to concentrate into already densely-populated areas. Urban soils often have hampered functioning due to various disturbances resulting from human activity. Innovative solutions are needed to bring the lacking ecosystem services and quality of life to these urban environments. For instance, the ecosystem services of the urban green infrastructure may be substantially improved through knowledge of their functional properties. In the research forming this thesis, the impacts of four plant species (Picea abies, Calluna vulgaris, Lotus corniculatus and Holcus lanatus) on belowground biota and regulatory ecosystem services were investigated in two different urban soil types. The retention of inorganic nitrogen and phosphorus in the plant-soil system, decomposition of plant litter, primary production, and the degradation of polycyclic aromatic hydrocarbons (PAHs) were examined in the field and under laboratory conditions. The main objective of the research was to determine whether the different plant species (representing traits with varying litter decomposability) will give rise to dissimilar urban belowground communities with differing ecological functions. Microbial activity as well as the abundance of nematodes and enchytraeid worm biomass was highest below the legume L. corniculatus. L. corniculatus and the grass H. lanatus, producing labile or intermediate quality litter, enhanced the proportion of bacteria in the soil rhizosphere, while the recalcitrant litter-producing shrub C. vulgaris and the conifer P. abies stimulated the growth of fungi. The loss of nitrogen from the plant-soil system was small for H. lanatus and the combination of C. vulgaris + P. abies, irrespective of their energy channel composition. These presumably nitrogen-conservative plant species effectively diminished the leaching losses from the plant-soil systems with all the plant traits present. The laboratory experiment revealed a difference in N allocation between the plant traits: C. vulgaris and P. abies sequestered significantly more N in aboveground shoots in comparison to L. corniculatus and H. Lanatus. Plant rhizosphere effects were less clear for phosphorus retention, litter decomposition and the degradation of PAH compounds. This may be due to the relatively short experimental durations, as the maturation of the plant-soil system is likely to take a considerably longer time. The empirical studies of this thesis demonstrated that the soil communities rapidly reflect changes in plant coverage, and this has consequences for the functionality of soils. The energy channel composition of soils can be manipulated through plants, which was also supported by the results of the separate meta-analysis conducted in this thesis. However, further research is needed to understand the linkages between the biological community properties and ecosystem services in strongly human-modified systems.

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The four papers summarized in this thesis deal with the Archean and earliest Paleoproterozoic granitoid suites observed in the Suomussalmi district, eastern Finland. Geologically, the area belongs to the Kianta Complex of the Western Karelian Terrane in the Karelian Province of the Fennoscandian shield. The inherited zircons up to 3440 Ma old together with Sm Nd and Pb Pb data confirm the existence of previously anticipated Paleoarchean protocrust in Suomussalmi. The general timeline of granitoid magmatism is similar to that of the surrounding areas. TTG magmatism occurred in three distinct phases: ca 2.95 Ga, 2.83 2.78 Ga and 2.76 2.74 Ga. In Suomussalmi the TTGs sensu stricto (K2O/Na2O less than 0.5) belong to the low-HREE type and are interpreted as partial melts of garnet amphibolites, which did not significantly interact with mantle peridotites. Transitional TTGs (K2O/Na2O more than 0.5), present in Suomussalmi and absent from surrounding areas, display higher LILE concentrations, but otherwise closely resemble the TTGs sensu stricto and indicate that recycling of felsic crust commenced in Suomussalmi 200 Ma earlier than in surrounding areas. The youngest TTG phase was coeval with the intrusion of the Likamännikkö quartz alkali feldspar syenite (2741 ± 2 Ma) complex. The complex contains angular fragments of ultrabasic rock, which display considerable compositional heterogeneity and are interpreted as cumulates containing clinopyroxene (generally altered to actinolite), apatite, allanite, epidote, and albite. The quartz alkali feldspar syenite cannot be regarded as alkaline sensu stricto, despite clear alkaline affinities. Within Likamännikkö there are also calcite carbonatite patches, which display mantle-like O- and C-isotope values, as well as trace element characteristics consistent with a magmatic origin, and could thus be among the oldest known carbonatites in the world. Sanukitoid (2.73 2.71 Ga) and quartz diorite suites (2.70 Ga) overlap within error margins and display compositional similarities, but can be differentiated from each other on the basis of higher Ba, K2O and LREE contents of the sanukitoids. The Likamännikkö complex, sanukitoids and quartz diorites are interpreted as originating from the metasomatized mantle and mark the diversification of the granitoid clan after 200 Ma of evolution dominated by the TTG suite. Widespread migmatization and the intrusion of anatectic leucogranitoids as dykes and intrusions of varying size took place at 2.70 2.69 Ga, following collisional thickening of the crust. The leucogranitoids and leucosomes of migmatized TTGs are compositionally alike and characterized by high silica contents and a leucocratic appearance. Due to compositional overlap, definitive discrimination between leucogranitoids and transitional TTGs requires isotope datings and/or knowledge of field relationships. Leucogranitoids represent partial melts of the local TTGs, both the sensu stricto and transitional types, mostly derived under water fluxed conditions, with possible fluid sources being late sanukitoids and quartz diorites as well as dehydrating lower crust. The Paleoproterozoic 2.44 2.39 Ga A-type granitoids of the Kianta Complex emplaced in an extensional environment are linked to the coeval and more widespread mafic intrusions and dykes observed over most of the Archean nucleus of the Fennoscandian shield. The A-type intrusions in the Suomussalmi area are interpreted as partial melts of the Archean lower crust and display differences in composition and magnetite content, which indicate differences in the composition and oxidation state of the source.

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Reorganizing a dataset so that its hidden structure can be observed is useful in any data analysis task. For example, detecting a regularity in a dataset helps us to interpret the data, compress the data, and explain the processes behind the data. We study datasets that come in the form of binary matrices (tables with 0s and 1s). Our goal is to develop automatic methods that bring out certain patterns by permuting the rows and columns. We concentrate on the following patterns in binary matrices: consecutive-ones (C1P), simultaneous consecutive-ones (SC1P), nestedness, k-nestedness, and bandedness. These patterns reflect specific types of interplay and variation between the rows and columns, such as continuity and hierarchies. Furthermore, their combinatorial properties are interlinked, which helps us to develop the theory of binary matrices and efficient algorithms. Indeed, we can detect all these patterns in a binary matrix efficiently, that is, in polynomial time in the size of the matrix. Since real-world datasets often contain noise and errors, we rarely witness perfect patterns. Therefore we also need to assess how far an input matrix is from a pattern: we count the number of flips (from 0s to 1s or vice versa) needed to bring out the perfect pattern in the matrix. Unfortunately, for most patterns it is an NP-complete problem to find the minimum distance to a matrix that has the perfect pattern, which means that the existence of a polynomial-time algorithm is unlikely. To find patterns in datasets with noise, we need methods that are noise-tolerant and work in practical time with large datasets. The theory of binary matrices gives rise to robust heuristics that have good performance with synthetic data and discover easily interpretable structures in real-world datasets: dialectical variation in the spoken Finnish language, division of European locations by the hierarchies found in mammal occurrences, and co-occuring groups in network data. In addition to determining the distance from a dataset to a pattern, we need to determine whether the pattern is significant or a mere occurrence of a random chance. To this end, we use significance testing: we deem a dataset significant if it appears exceptional when compared to datasets generated from a certain null hypothesis. After detecting a significant pattern in a dataset, it is up to domain experts to interpret the results in the terms of the application.